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0~3岁婴幼儿家长托育服务需求现状及优化策略——基于Kano模型的分析 被引量:5
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作者 勾嘉雯 刘丽伟 +1 位作者 张可欣 尹晨 《学前教育研究》 CSSCI 北大核心 2024年第4期54-72,共19页
托育服务是我国老龄少子化背景下重要的民生工程。为探讨0~3岁婴幼儿家长对托育服务的需求层次结构并对托育服务提出对策建议,本研究基于魅力质量理论与Kano模型,通过访谈法与现有文献资料确定了0~3岁婴幼儿家长对托育服务的6个需求维度... 托育服务是我国老龄少子化背景下重要的民生工程。为探讨0~3岁婴幼儿家长对托育服务的需求层次结构并对托育服务提出对策建议,本研究基于魅力质量理论与Kano模型,通过访谈法与现有文献资料确定了0~3岁婴幼儿家长对托育服务的6个需求维度与41个需求要素。本研究通过Kano问卷收集0~3岁婴幼儿家长的托育服务需求信息,根据Better-Worse系数与平均满意度指标(ASC)确定了2个基本型需求维度、2个期待型需求维度、1个魅力型需求维度、1个无差异型需求维度以及12个基本型需求要素、8个期待型需求要素、13个魅力型需求要素、8个无差异型需求要素及其重要性排序,并据此对家庭托育服务需求特点开展讨论。基于上述分析,研究提出了以下四条托育服务优化策略:完善机构监督制度,保障托育服务质量;健全师资准入培训,提高托育人员素养;做好个性需求管理,提供多元服务形式;加大政策宣传普及,加快普惠托育建设。 展开更多
关键词 0~3岁托育服务 托育需求 KAno模型 魅力质量理论
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Clinical outcome and prognostic factors of T4N0M0 colon cancer after R0 resection:A retrospective study 被引量:1
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作者 Bang Liu Zhao-Xiong Zhang +3 位作者 Xin-Yang Nie Wei-Lin Sun Yong-Jia Yan Wei-Hua Fu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期1869-1877,共9页
BACKGROUND Paradoxically,patients with T4N0M0(stage II,no lymph node metastasis)colon cancer have a worse prognosis than those with T2N1-2M0(stage III).However,no previous report has addressed this issue.AIM To screen... BACKGROUND Paradoxically,patients with T4N0M0(stage II,no lymph node metastasis)colon cancer have a worse prognosis than those with T2N1-2M0(stage III).However,no previous report has addressed this issue.AIM To screen prognostic risk factors for T4N0M0 colon cancer and construct a prognostic nomogram model for these patients.METHODS Two hundred patients with T4N0M0 colon cancer were treated at Tianjin Medical University General Hospital between January 2017 and December 2021,of which 112 patients were assigned to the training cohort,and the remaining 88 patients were assigned to the validation cohort.Differences between the training and validation groups were analyzed.The training cohort was subjected to multi-variate analysis to select prognostic risk factors for T4N0M0 colon cancer,followed by the construction of a nomogram model.RESULTS The 3-year overall survival(OS)rates were 86.2%and 74.4%for the training and validation cohorts,respectively.Enterostomy(P=0.000),T stage(P=0.001),right hemicolon(P=0.025),irregular review(P=0.040),and carbohydrate antigen 199(CA199)(P=0.011)were independent risk factors of OS in patients with T4N0M0 colon cancer.A nomogram model with good concordance and accuracy was constructed.CONCLUSION Enterostomy,T stage,right hemicolon,irregular review,and CA199 were independent risk factors for OS in patients with T4N0M0 colon cancer.The nomogram model exhibited good agreement and accuracy. 展开更多
关键词 T4N0M0 colon cancer PROGnoSIS Multivariate analysis noMOGRAM Colon cancer
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Simultaneous catalytic removal of NOx and diesel PM over La_(0.9) K_(0.1) CoO_3 catalyst assisted by plasma 被引量:1
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作者 PEIMei-xiang LINHe SHANGGUANWen-feng HUANGZhen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期220-223,共4页
The simultaneous removal of NOx and particulate matter(PM) from diesel exhaust is investigated over a mixed metal oxide catalyst of La 0.9 K 0.1 CoO 3 loaded on γ-Al 2O 3 spherules with the assistant of pl... The simultaneous removal of NOx and particulate matter(PM) from diesel exhaust is investigated over a mixed metal oxide catalyst of La 0.9 K 0.1 CoO 3 loaded on γ-Al 2O 3 spherules with the assistant of plasma. It was found that NOx was reduced by PM in oxygen rich atmosphere, the CO 2 and N 2 were produced in the same temperature window without considering the N 2 formed by plasma decomposition. As a result, the temperature for the PM combustion decreases and the reduction efficiency of NOx to N 2 increases during the plasma process, which indicated that the activity of the catalyst can be improved by plasma. The NOx is decomposed by plasma at both low temperature and high temperature. Therefore, the whole efficiency of NOx conversion is enhanced. 展开更多
关键词 simultaneous removal plasma assisted catalysis nox PM diesel
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Multi-Body Dynamics Analysis and Low Noise Optimization of X6170ZC Diesel 被引量:3
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作者 孙少军 郑勇 +1 位作者 倪广健 张俊红 《Transactions of Tianjin University》 EI CAS 2007年第4期297-302,共6页
The multi-body dynamics model of the X6170ZC diesel is established to analyze vibration and acoustic noise. The high quality finite element and simulation models are developed, and nonlinear springs are used to imitat... The multi-body dynamics model of the X6170ZC diesel is established to analyze vibration and acoustic noise. The high quality finite element and simulation models are developed, and nonlinear springs are used to imitate the joints of engine components. The acoustic behavior of the structure is evaluated by the velocity of surface vibration. The noise level is reduced by improving the structure of the engine. The result shows that the surface vibration velocity level is decreased about 3.7 dB (A) at 1 600 Hz after the optimization. Based on the contrast between the two structures, it is concluded that through structure design the combined noise can be reduced, and the virtual design mode of diesel engines is feasible. 展开更多
关键词 diesel engine DYNAMICS VIBRATION acoustic noise OPTIMIZATION
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Factors Associated with Acute Respiratory Infections in Children Aged 0 - 5 Years in the Yénawa District of Cotonou (Benin) in 2023
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作者 Virginie Mongbo Luc Béhanzin +2 位作者 Lamidhi Salami Nicolas Hamondji Amegan Edgard-Marius Ouendo 《Open Journal of Epidemiology》 2024年第2期331-342,共12页
Introduction: Acute respiratory infections remain one of the main causes of mortality in children aged 0 to 5. This work aimed to study the associated factors with the occurrence of acute respiratory infections in chi... Introduction: Acute respiratory infections remain one of the main causes of mortality in children aged 0 to 5. This work aimed to study the associated factors with the occurrence of acute respiratory infections in children 0 to 5 years old in Yénawa, Cotonou in 2023. Subjects and Method: It was an analytical cross-sectional study of children aged 0 - 5 years and their mothers in Yénawa, selected by four-degree random sampling. The sampling size, calculated using the Schwartz formula, was 126 children and 126 mothers. The dependent variable was the occurrence of acute respiratory infections. The independent variables were classified into four groups: socio-demographic and economic characteristics, behavioral factors, child-related factors, and environmental factors. Data collected by observation and questionnaire survey were analyzed using STATA version 15 software. Associated factors were investigated by bivariate analysis and multiple logistic regression, at the 5% significance level. Results: A total of 126 children aged 0 - 5 years and 126 mothers were surveyed, aged 23.5 (11 - 36) months and 30 (18 - 48) years respectively. The prevalence of acute respiratory infections was 74.60% (CI95% = 66.89 to 82.30). The associated factors were the mother’s age between 18 and 28 (OR = 10.77;CI95% = 1.89 to 61.27;p = 0.007), the use of charcoal/wood for cooking (OR = 7.36;IC = 1.99 to 27.10;p = 0.003)), children's poor personal hygiene (OR = 8.87;IC = 2.92 to 26.97;p 0.001)), and cohabitation with domestic animals (OR = 7.27;IC = 1.67 to 31.71;p = 0.015). Conclusion: Communicating with mothers about the factors identified will help reduce the prevalence of acute respiratory infections in children aged 0 to 5. 展开更多
关键词 Acute Respiratory Infections Children Aged 0 - 5 Associated Factors Yénawa BENIN
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Occupational Carbon Monoxide Poisoning Associated with Diesel Motor Operation in an Air-raid Shelter in June 2015, Jinan City, China-An Epidemiological Investigation 被引量:4
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作者 CUI Liang Liang ZHOU Jing Wen +4 位作者 GENG Xing Yi LI Xin Wei LIU Zhong George A.Conway ZHANG Ji 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第10期777-781,共5页
Carbon monoxide (CO) is an odorless, colorless gas produced by incomplete combustion of carbonbased compounds. Exposure to CO can cause various adverse health effects ranging from headache and fatigue to coma and de... Carbon monoxide (CO) is an odorless, colorless gas produced by incomplete combustion of carbonbased compounds. Exposure to CO can cause various adverse health effects ranging from headache and fatigue to coma and death. Thousands of illnesses and deaths have been documented through CO poisoning surveillance systems and accident investigations each year. 展开更多
关键词 CO ARS Occupational Carbon Monoxide Poisoning Associated with diesel Motor Operation in an Air-raid Shelter in June 2015 Jinan City China An Epidemiological Investigation
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Determination of Technological Condition of Diesel Engine PZ12V190B Using Fuzzy Method
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作者 WangZhaohui ZhangLaibin ZhangBingzhong 《Petroleum Science》 SCIE CAS CSCD 2004年第1期55-58,共4页
This article has selected useful diagnostic parameters according to the running condition of PZ12V190B diesel, and built fuzzy vectors of this parameter by using the subjection function to establish a technological co... This article has selected useful diagnostic parameters according to the running condition of PZ12V190B diesel, and built fuzzy vectors of this parameter by using the subjection function to establish a technological condition. By using a statistical method the standard vector has been obtained, so the diesel technological level can be determined by calculating the closing degree between the fuzzy vector and the standard fuzzy vector. 展开更多
关键词 Fuzzy diagnosis diesel engine technological condition
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Removal of NO_x and Diesel Soot Particulates Catalyzed byPerovskite-type Oxide La_(0.9)K_(0.1)CoO_3
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作者 王伟 ZHAN Reggie 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第1期57-59,共3页
The catalytic performance of perovskite composite oxide catalyst La0.9 K0.1 CoO3 coated on catalyst supports by traditional solid state reaction method and sol-gel method were investigated by a series of experiments.... The catalytic performance of perovskite composite oxide catalyst La0.9 K0.1 CoO3 coated on catalyst supports by traditional solid state reaction method and sol-gel method were investigated by a series of experiments. The restdt shows that the catalytic performance of the La0.9 K0.1 CoO3 perovskite composite oxide catalyst synthesized by sol-gel method is superior to that synthesized by solid state reaction method, having lower ignition temperature of the diesel soot particulates, lower start temperature of NOx treatment, and lower concentration of byproduct CO. 展开更多
关键词 perovskite composite oxides La0.9 K0.1 CoO3 sol-gel method diesel waste gas cleaning
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Study of the Viscosity and Specific Gravity of the Ternary Used Frying Oil (UFO)-Bioethanol-Diesel System
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作者 Konan Edmond Kouassi Abollé Abolle +3 位作者 N’guessan Luc Brou David Boa N’guessan Raymond Kre Kouassi Benjamin Yao 《Journal of Materials Science and Chemical Engineering》 2024年第4期53-66,共14页
Fossil fuels cover around 80% of global energy consumption. However, the problems linked to their use justify the choice of using biofuel. In order to reduce as much as possible, diesel rate, an increase in the number... Fossil fuels cover around 80% of global energy consumption. However, the problems linked to their use justify the choice of using biofuel. In order to reduce as much as possible, diesel rate, an increase in the number of additives may be considered. Thus, in this work, the study of the used frying oil (UFO), bioethanol and diesel ternary system was undertaken. It emerges from this study that the addition of bioethanol reduces the viscosity and the density of the ternary system and permits a 90% substitution rate for diesel between the UFO and bioethanol. Finally, the percentage of oil becomes 40% after adding alcohol compared to the binary diesel crude vegetable oil mixture where this rate is 30%. 展开更多
关键词 Biofuel UFO-Bioethanol-diesel Ternary Density VISCOSITY
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No.0柴油水溶组分海洋浮游植物生态效应研究 被引量:6
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作者 李克强 王修林 +4 位作者 祝陈坚 石晓勇 胡海燕 李瑞香 孙胜玉 《环境科学》 EI CAS CSCD 北大核心 2007年第2期304-308,共5页
应用现场和实验室培养方法,研究了No.0柴油水溶组分海洋浮游植物生态效应.提出了摄食条件下的海洋浮游植物生长模型和不同浓度No.0柴油水溶组分下浮游植物生长效应模型,分析了不同浓度No.0柴油水溶组分下浮游植物生长效应.结果表明,摄... 应用现场和实验室培养方法,研究了No.0柴油水溶组分海洋浮游植物生态效应.提出了摄食条件下的海洋浮游植物生长模型和不同浓度No.0柴油水溶组分下浮游植物生长效应模型,分析了不同浓度No.0柴油水溶组分下浮游植物生长效应.结果表明,摄食条件下的海洋浮游植物生长模型较传统Logistic模型能更好地反映海洋生态系统,同时应用非线性拟合技术得到了不同浓度No.0柴油水溶组分下海洋浮游植物终止生物量(Bf).根据海洋浮游植物生长效应模型进一步分析表明,在现场和实验室条件下,低浓度No.0柴油水溶组分对浮游植物生长有明显促进作用,生长促进率最大分别约为180%和120%,然而,在高浓度No.0柴油水溶组分条件下,石油烃对浮游植物生长效应不甚显著,甚至有明显抑制作用. 展开更多
关键词 no.0柴油水溶组分 浮游植物 生长效应 模型
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MnO_x/α-Al_2O_3催化氧化燃煤烟气中Hg^0的试验研究 被引量:15
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作者 乔少华 晏乃强 +2 位作者 陈杰 瞿赞 贾金平 《中国环境科学》 EI CAS CSCD 北大核心 2009年第3期237-241,共5页
在模拟烟气中研究了MnOx/α-Al2O3催化剂对烟气零价汞(Hg0)的催化氧化效果,以及反应条件对Hg0氧化率的影响.结果表明,300℃时催化剂的活性最大,模拟烟气含有20mL/m3HCl时Hg0的氧化率达到91%.在8000~32000h-1空速范围内,Hg0氧化率保持在... 在模拟烟气中研究了MnOx/α-Al2O3催化剂对烟气零价汞(Hg0)的催化氧化效果,以及反应条件对Hg0氧化率的影响.结果表明,300℃时催化剂的活性最大,模拟烟气含有20mL/m3HCl时Hg0的氧化率达到91%.在8000~32000h-1空速范围内,Hg0氧化率保持在90%以上;空速提高到96000h-1时,氧化率开始下降,并与空速成反比.烟气中的SO2与HCl竞争催化剂上的活性位,对催化氧化反应有一定抑制,500mL/m3SO2使零价汞的氧化率下降约20%.此外,还对MnOx催化氧化零价汞的反应机制进行了探讨. 展开更多
关键词 燃煤烟气 Hg0 锰氧化物 催化氧化
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Heterogeneous catalytic activation of peroxymonosulfate for efficient degradation of organic pollutants by magnetic Cu^0/Fe_3O_4 submicron composites 被引量:10
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作者 聂刚 黄佳 +3 位作者 胡冶州 丁耀彬 韩小彦 唐和清 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期227-239,共13页
Magnetic Cu^0/Fe3O4 submicron composites were prepared using a hydrothermal method and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS) and the degradation of organic pollutants.The as-pr... Magnetic Cu^0/Fe3O4 submicron composites were prepared using a hydrothermal method and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS) and the degradation of organic pollutants.The as-prepared magnetic Cu^0/Fe3O4 submicron composites were composed of Cu^0 and Fe3O4 crystals and had an average size of approximately 220 nm.The Cu^0/Fe3O4 composites could efficiently catalyze the activation of PMS to generate singlet oxygen,and thus induced the rapid degradation of rhodamine B,methylene blue,orange Ⅱ,phenol and 4-chlorophenol.The use of0.1 g/L of the Cu^0/Fe3O4 composites induced the complete removal of rhodamine B(20 μmol/L) in15 min,methylene blue(20 μmol/L) in 5 min,orange Ⅱ(20 μmol/L) in 10 min,phenol(0.1mmol/L) in 30 min and 4-chlorophenol(0.1 mmol/L) in 15 min with an initial pH value of 7.0 and a PMS concentration of 0.5 mmol/L.The total organic carbon(TOC) removal higher than 85%for all of these five pollutants was obtained in 30 min when the PMS concentration was 2.5 mmol/L.The rate of degradation was considerably higher than that obtained with Cu^0 or Fe3O4 particles alone.The enhanced catalytic activity of the Cu^0/Fe3O4 composites in the activation of PMS was attributed to the synergistic effect of the Cu^0 and Fe3O4 crystals in the composites.Singlet oxygen was identified as the primary reactive oxygen species responsible for pollutant degradation by electron spin resonance and radical quenching experiments.A possible mechanism for the activation of PMS by Cu^0/Fe3O4 composites is proposed as electron transfer from the organic pollutants to PMS induces the activation of PMS to generate ^1O2,which induces the degradation of the organic pollutants.As a magnetic catalyst,the Cu^0/Fe3O4 composites were easily recovered by magnetic separation,and exhibited excellent stability over five successive degradation cycles.The present study provides a facile and green heterogeneous catalysis method for the oxidative removal of organic pollutants. 展开更多
关键词 Heterogeneous catalysis Magnetic Cu^0/Fe3O4 composite PEROXYMOnoSULFATE Singlet oxygen Oxidative degradation
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Tessier No.0面裂分叉鼻畸形矫正术 被引量:1
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作者 冯国平 李太颖 +2 位作者 滕利 孙广慈 周刚 《中国美容整形外科杂志》 CAS 2006年第4期254-256,共3页
目的探讨一种有关TessierNo.0面裂分叉鼻畸形矫正术的改良方法。方法在鼻小柱和鼻翼沟处设计“蝶”型切口,将鼻小柱、鼻背部皮肤及其下的软骨等深部组织钝性剥离,暴露像书页一样翻向两侧的双层鼻中隔软骨,充分分离后将两侧的鼻中隔软骨... 目的探讨一种有关TessierNo.0面裂分叉鼻畸形矫正术的改良方法。方法在鼻小柱和鼻翼沟处设计“蝶”型切口,将鼻小柱、鼻背部皮肤及其下的软骨等深部组织钝性剥离,暴露像书页一样翻向两侧的双层鼻中隔软骨,充分分离后将两侧的鼻中隔软骨对拢缝合,同时采取将中央部位的鼻中隔软骨用于加强鼻小柱和加高鼻端、鼻背部。通过两侧的鼻翼沟切口,切除鼻端多余的皮肤,用碘仿纱条填塞鼻腔。结果采用本方法进行5例TessierNo.0面裂分叉鼻矫正术,外鼻形态满意,切口隐蔽,效果良好。结论手术采用改良的“蝶”型切口可同时达到延长鼻小柱、加高鼻端部、切除鼻端部的多余皮肤,切口隐蔽;双层鼻中隔软骨可以作为软骨的供区。 展开更多
关键词 Tessier no.0面裂 分叉鼻 改良“蝶”型切口 软骨移植
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富锂正极材料0.5Li_2MnO_3·0.5LiCoO_2的熔盐法合成及改性 被引量:3
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作者 赵煜娟 任文锋 +2 位作者 吴锐 孙玉成 岳影影 《现代化工》 CAS CSCD 北大核心 2013年第8期53-57,59,共6页
通过熔盐法合成富锂正极材料0.5Li2MnO3.0.5LiCoO2,以低熔点盐为原料,低温熔融混合,分别研究了不同热处理方式和锂配比对富锂正极材料0.5Li2MnO3.0.5LiCoO2的结构、形貌和电化学性能的影响。结果表明:采用化学计量比的锂盐,低温200℃预... 通过熔盐法合成富锂正极材料0.5Li2MnO3.0.5LiCoO2,以低熔点盐为原料,低温熔融混合,分别研究了不同热处理方式和锂配比对富锂正极材料0.5Li2MnO3.0.5LiCoO2的结构、形貌和电化学性能的影响。结果表明:采用化学计量比的锂盐,低温200℃预处理后,高温短时间处理,可以得到粒径均一和层状结构良好的材料。为了提高材料的循环性能,通过熔盐法对富锂正极材料0.5Li2MnO3.0.5LiCoO2进行氟离子掺杂。结果表明:氟离子掺杂后,材料的循环性能和倍率性能均得到提高;同时,在大电流下,氟离子掺杂减缓了容量缓升现象,缩短了活化时间。 展开更多
关键词 锂离子电池 0 5Li2Mno3·0 5LiCoO2 熔盐合成 氟离子掺杂
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One-step hydrothermal synthesis of Cu-SAPO-34/cordierite and its catalytic performance on NO_x removal from diesel vehicles 被引量:2
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作者 王建成 陈影 +3 位作者 唐磊 鲍卫仁 常丽萍 韩丽娜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3330-3336,共7页
Cu-SAPO-34/cordierite catalysts were prepared via one-step hydrothermal synthesis method and their performances to remove NO x from the diesel vehicle exhaust were evaluated. The morphology, structure, Cu content and ... Cu-SAPO-34/cordierite catalysts were prepared via one-step hydrothermal synthesis method and their performances to remove NO x from the diesel vehicle exhaust were evaluated. The morphology, structure, Cu content and valence state were characterized by SEM, XRD, ICP and XPS, respectively. The experimental results show the active component Cu of the catalysts via in situ synthesis could significantly improve the selective catalytic reduction (SCR) activities of NOx and the optimal Cu content is in the range of 0.30%-0.40%(mass fraction). No N 2 O is detected by gas chromatograph (GC) during the evaluation process, which implies that NOx is almost entirely converted to N2 over Cu-SAPO-34/cordierite catalyst. The conversion rate of NOx to N2 by NH3 over catalyst could almost be up to 100%in the temperature range of 300-670 ℃with a space velocity of 12000 h-1 and it is still more than 60% at 300-620 ℃ under 36000 h-1. The catalysts also show the good hydrothermal and chemical stability at the atmosphere with H 2 O. 展开更多
关键词 in situ synthesis Cu-SAPO-34/cordierite nox selective catalyst reduction NH3 diesel vehicle exhaust
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KMnO_4溶液改性半焦对烟气中气态Hg^0的吸附性能研究 被引量:9
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作者 王力 陈继涛 +3 位作者 张华伟 李敏 张林林 刘珊珊 《燃料化学学报》 EI CAS CSCD 北大核心 2012年第12期1498-1504,共7页
在小型固定床实验台上利用半焦及其KMnO4溶液改性样品进行气态Hg0吸附实验。结果表明,在低温时原料半焦对气态Hg0具有良好的吸附性能,升温则使其吸附性能迅速降低;经高锰酸钾溶液浸渍处理后,改性半焦在高温140℃时吸附性能明显提高,对... 在小型固定床实验台上利用半焦及其KMnO4溶液改性样品进行气态Hg0吸附实验。结果表明,在低温时原料半焦对气态Hg0具有良好的吸附性能,升温则使其吸附性能迅速降低;经高锰酸钾溶液浸渍处理后,改性半焦在高温140℃时吸附性能明显提高,对浸渍样品在250℃进行热处理可使其吸附性能进一步提高。BET结果表明,原料半焦具有较发达的微孔结构,改性处理使微孔比例下降,孔隙结构发达程度降低;XPS测试表明,改性半焦表面的汞主要以氧化态(Hg2+)形式存在,高价锰化合物(KMnO4、K2MnO4、MnO2)是主要的氧化活性物质。 展开更多
关键词 改性半焦 KMno4溶液 气态Hg0 烟气脱汞 吸附性能
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MnO_2·0.5H_2O的固相法制备及其对Li^+的吸附动力学 被引量:11
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作者 石西昌 张志兵 +3 位作者 周喜诚 周定方 肖湘 陈白珍 《中国有色金属学报》 EI CAS CSCD 北大核心 2012年第11期3135-3143,共9页
采用两步固相法制备锂离子筛MnO2.0.5H2O,采用X射线衍射仪和相关动力学模型研究MnO2.0.5H2O的结构及其吸附性能,探讨离子筛对盐湖卤水中各主要金属离子的分离特性及循环吸附性能。结果表明:溶液pH值的升高有利于离子筛对Li+的吸附,但在... 采用两步固相法制备锂离子筛MnO2.0.5H2O,采用X射线衍射仪和相关动力学模型研究MnO2.0.5H2O的结构及其吸附性能,探讨离子筛对盐湖卤水中各主要金属离子的分离特性及循环吸附性能。结果表明:溶液pH值的升高有利于离子筛对Li+的吸附,但在较强的碱性溶液中离子筛的溶损相应增加;吸附数据对伪二级动力学方程和Langmuir吸附等温方程拟合较好,相关系数分别达0.998和0.993以上;动边界模型中各控制步骤方程的线性拟合都不够理想;离子筛对Li+具有较好的选择性和较优的循环吸附性能。这表明:吸附过程为化学吸附过程,且为单层吸附;吸附过程是一个复杂过程,是多个控制步骤共同作用的结果。 展开更多
关键词 锂离子筛 Mno2 0 5H2O 固相法 动力学 吸附
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LiSbO3含量对BiMnO3掺杂K(0.5)Na(0.5)NbO3陶瓷的结构与压电性能的影响研究 被引量:1
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作者 江民红 刘心宇 +3 位作者 陈国华 朱归胜 许积文 马家峰 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2013年第3期321-325,共5页
采用传统陶瓷常压烧结工艺制备(0.996–x)KNN-0.004BM-xLS(x=0、0.01、0.02、0.03、0.04、0.05、0.06)无铅压电陶瓷,着重研究了LS的含量对(0.996–x)KNN-0.004BM-xLS陶瓷相结构和压电性能的影响。结果表明,当x≤0.02时,陶瓷具有单一的... 采用传统陶瓷常压烧结工艺制备(0.996–x)KNN-0.004BM-xLS(x=0、0.01、0.02、0.03、0.04、0.05、0.06)无铅压电陶瓷,着重研究了LS的含量对(0.996–x)KNN-0.004BM-xLS陶瓷相结构和压电性能的影响。结果表明,当x≤0.02时,陶瓷具有单一的正交相结构;当0.03≤x≤0.05时,陶瓷具有正交相与四方相共存的过渡结构;当x=0.06时,陶瓷具有单一的四方相结构。陶瓷的MPB成分范围在0.03≤x≤0.05。随着LS含量的增加,陶瓷材料的d33和kp均先增加后减小,当x=0.05时,均达到最大值,分别为230 pC/N和0.42;陶瓷的To-t和Tc均向低温方向移动;当x=0时,陶瓷的To-t和Tc分别为455和215℃;当x=0.02时,陶瓷的To-t和Tc分别为385和150℃;当x=0.06时,To-t和Tc分别降至370℃和75℃。 展开更多
关键词 无铅压电陶瓷 K0 5Na0 5NbO3 BiMno3 LiSbO3 压电性能
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La_(0.67)Ca_(0.33)MnO_3电子自旋共振线宽的自旋波理论 被引量:1
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作者 胡小颖 付志雄 +1 位作者 何畏 赵利军 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2013年第2期305-308,共4页
采用固相反应法制备巨磁电阻材料La0.67Ca0.33MnO3,测试其电子自旋共振,并采用自旋波理论解释自旋共振线宽的变化.通过对自旋波能量的计算机自洽计算,得到了自旋相互作用的重正化因子{1-e(T)/S},重正化因子随体系温度升高而降低表明,温... 采用固相反应法制备巨磁电阻材料La0.67Ca0.33MnO3,测试其电子自旋共振,并采用自旋波理论解释自旋共振线宽的变化.通过对自旋波能量的计算机自洽计算,得到了自旋相互作用的重正化因子{1-e(T)/S},重正化因子随体系温度升高而降低表明,温度上升导致自旋波频率发生软化现象,使得体系结构不稳定,由此可知实验未探测到相变区自旋波能量的原因.理论计算表明,自旋共振线宽随温度升高而减小是由于自旋波耦合模的数目减少所致. 展开更多
关键词 LA0 67Ca0 33Mno3 电子自旋共振线宽 自旋波理论
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xLi_2MnO_3-(1-x)LiNi_(0.7)Co_(0.3)O_2的低温燃烧合成及电化学性能研究 被引量:2
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作者 吴保明 叶乃清 +2 位作者 马真 韩建峰 徐东 《无机化学学报》 SCIE CAS CSCD 北大核心 2013年第9期1835-1841,共7页
采用低温燃烧法合成了锂离子电池正极材料xLi2MnO3-(1-x)LiNi0.7Co0.3O2,对合成产物的结构、形貌和电化学性能进行了系统的研究,通过单因素试验对合成条件和材料的组成进行了优化。结果表明:采用低温燃烧法合成的富锂层状正极材料具有α... 采用低温燃烧法合成了锂离子电池正极材料xLi2MnO3-(1-x)LiNi0.7Co0.3O2,对合成产物的结构、形貌和电化学性能进行了系统的研究,通过单因素试验对合成条件和材料的组成进行了优化。结果表明:采用低温燃烧法合成的富锂层状正极材料具有α-NaFeO2型层状结构、球状形貌和良好的电化学性能;其最佳合成条件为:回火温度850℃,回火时间20 h;Li2MnO3的最佳配比为x=0.7。在此条件下合成的0.7Li2MnO3-0.3LiNi0.7Co0.3O2,最高放电比容量达到263.1 mAh.g-1,并具有良好的循环性能和倍率性能。 展开更多
关键词 锂离子电池 正极材料 xLi2Mno3-(1-x)LiNi0 7Co0 3O2 低温燃烧合成
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